This invention relates to a retainer assembly for retaining medical instruments. It relates especially to a retainer assembly capable of holding medical instruments at fixed positions in a tray or other container while maintaining sterile conditions within the container.
There exists in the prior art various retainers and accessories for fixing the positions of articles of one kind or another. These include hooks, pegs, clips, brackets, etc. Such retainers may be used in a wide variety of applications. For example, they are commonly used in the medical field to fix the positions of various surgical instruments, devices and prostheses while those articles are being transported, sterilized and processed in one way or another. Accordingly, we will describe the invention in that context. It should be understood, however, that the present invention has application in other fields is besides the medical field.
Medical instruments are often transported in trays. Prior to use, such instruments are placed in the tray and subjected to sterilization. To improve the circulation of steam throughout the tray, the tray bottom wall and perhaps also the side wall are usually perforated. In order to maintain a separation between the various instruments in the tray, the instruments are supported or retained by posts, brackets or other retainers anchored to the tray. Following sterilization, the tray full of instruments may be transported to an operating room and placed close to a surgical team whose members may withdraw the instruments from the tray as needed for the particular surgical procedure being performed. Usually, the instruments are selectively arranged or organized in the tray so that they can be picked from the tray in the order in which they are needed for the particular procedure. Examples of such trays are disclosed in my U.S. Pat. Nos. 5,424,048 and 5,681,539.
FIG. 1 depicts a typical medical tray shown generally at 10. The tray has a bottom wall 10a and side walls 10b extending up from the bottom wall to define a generally rectangular interior space 12. The tray is usually made of a material able to with stand sterilization, e.g. polyphenylsulphone or a non-corroding metal such as aluminum, stainless steel or titanium. The bottom wall 10a of tray 10 is usually formed with a multiplicity of vent holes 16 arranged in columns and rows to allow for circulation of steam or other sterilizing fluid throughout the interior space 12. As will be described in more detail presently, these holes may also function as anchoring points for the retainers and accessories used to locate various medical instruments within tray 10.
Tray 10 is adapted to contain a plurality of variously shaped medical instruments I. In order to retain these instruments in the tray, assorted retainers or accessories may be employed. These may include known solitary post assemblies 18 as well as conventional elongated retainer assemblies 20 and 20′ having notches or slots for receiving instruments I as shown.
As depicted in FIGS. 1 and 2A, the retainer assembly 20 comprises a unitary retainer 22 molded of a rigid plastic material able to withstand sterilization. The retainer is in the form of an upstanding blade containing notches or slots 22a and having a bottom flange 24 so that the retainer has the general shape of an inverted letter T. Threaded holes 26 extend up from the bottom of retainer 22. These holes are spaced apart along the retainer a distance that is an integral multiple of the spacing between the holes 16 in a given row of holes in tray bottom wall 10a. Thus, retainer 22 may be positioned on the tray wall 10a with its holes 26 in alignment with the vent holes 16 in the tray so that the other components of the assembly 20, namely threaded fasteners 28, may be inserted through the vent holes and turned down into the registering holes 26 in retainer 22 as shown in FIG. 2A.
Instead of being a unitary part as depicted in FIG. 2A, some conventional retainers are composed of two separate pieces which are keyed together. A retainer such as this is shown generally at 22′ in FIGS. 1 and 2B. That retainer comprises a rigid rail 32 molded of a suitable hard plastic material able to withstand sterilization. Spaced-apart threaded holes 34 extend up from the bottom of rail 32 for receiving threaded fasteners 28 to secure the rail to the tray bottom wall 10a in the same manner as retainer 22 described above.
Rail 32 is adapted to receive and support a blade-like instrument holder 38 made of a flexible, resilient, sterilizable material such as silicone. The holder 38 may be formed with slits or cut-outs 38a for holding medical instruments I. In order to mechanically secure the holder 38 to rail 32, the bottom of the holder is flanged to form a key 40 which is shaped and sized to slidably engage in a keyway 42 formed in the upper portion of rail 32.
The posts of assemblies 18 depicted in FIG. 1 may be anchored in a similar fashion to the tray bottom wall 10a using threaded fasteners 28.
Although these prior retainer assemblies perform their instrument retaining function satisfactorily, they may not pass new safety requirements being proposed by the FDA to ensure that medical trays and their contents are free from contamination. That is, more emphasis is being placed on being able to demonstrate the ability to thoroughly clean and sterilize such products. The FDA is particularly concerned with cleaning and sterilization at mating surfaces such as the undersurfaces of the retainer 22 and rail 32 where they meet the tray wall 10a, as well as the opposing surfaces at the boundary between the silicone holder 38 and the rail 32 of the retainer assembly 20′ shown in FIG. 2B. If that holder 38 is flexed laterally, an appreciable may open between the holder and the rail. All of these locations have the possibility of trapping bacterial contamination and protecting same during the sterilization process. In fact, the only way to ensure a proper cleaning of these surfaces is to dissemble all of the retainer assemblies and remove them from the tray 10 so that all of the parts can be sterilized separately. Of course, all of the retainer parts must then be reassembled in the tray for the next operation. Needless to say, this is a tedious task and is not desirable from the standpoint of efficiency. Also, in their disassembled state, the various small parts may be misplaced or lost while being processed.